Class SearchRequestor

Collects the results from a search engine query.
Clients implement a subclass to pass to SearchEngine.search
and implement the acceptSearchMatch(SearchMatch) method, and
possibly override other life cycle methods.

The search engine calls beginReporting() when a search starts,
then calls acceptSearchMatch(...) for each search result, and
finally calls endReporting(). The order of the search results
is unspecified and may vary from request to request; when displaying results,
clients should not rely on the order but should instead arrange the results
in an order that would be more meaningful to the user.